Co‐occurring medical conditions in adults with Down syndrome: A systematic review toward the development of health care guidelines. Part II

Adults with Down syndrome (DS) represent a unique population who are in need of clinical guidelines to address their medical care. Many of these conditions are of public health importance with the potential to develop screening recommendations to improve clinical care for this population. Our workgroup previously identified and prioritized co‐occurring medical conditions in adults with DS. In this study, we again performed detailed literature searches on an additional six medical conditions of clinical importance. A series of key questions (KQ) were formulated a priori to guide the literature search strategy. Our KQs focused on disease prevalence, severity, risk‐factors, methodologies for screening/evaluation, impact on morbidity, and potential costs/benefits. The available evidence was extracted, evaluated and graded on quality. The number of participants and the design of clinical studies varied by condition and were often inadequate for answering most of the KQ. Based upon our review, we provide a summary of the findings on hip dysplasia, menopause, acquired cardiac valve disease, type 2 diabetes mellitus, hematologic disorders, and dysphagia. Minimal evidence demonstrates significant gaps in our clinical knowledge that compromises clinical decision‐making and management of these medically complex individuals. The creation of evidence‐based clinical guidance for this population will not be possible until these gaps are addressed.     

Concentrated gram stain smears prepared with a cytospin centrifuge.

A Cytospin slide centrifuge was used to concentrate 0.05- to 0.5-ml samples of cerebrospinal and other body fluids for Gram stain. Trials with cerebrospinal fluid containing known numbers of microorganisms indicated that the Cytospin increased the sensitivity of cerebrospinal fluid Gram stains by up to 2 logs compared with unconcentrated and conventional centrifuge smears. Cytospin-concentrated smears were prospectively compared with unconcentrated Gram-stained smears and bacteriological culture results for 80 clinical body fluid specimens. Bacteria were seen in unconcentrated smears of 9 of the 16 (56%) fluids which were infected, whereas Cytospin smears of 12 of the 16 (75%) showed bacteria. Cytospin smears revealed more bacteria and demonstrated better leukocyte morphology than did unconcentrated or conventionally centrifuged samples of small volumes of infected body fluids, allowing early diagnosis of infection.     

Pattern and predictors of weight gain during pregnancy among HIV-1-infected women from Tanzania

Progression of HIV disease is often accompanied by weight loss and wasting. Gestational weight gain is a strong determinant of maternal and neonatal outcomes; however, the pattern and predictors of weight gain during pregnancy among HIV-positive women are unknown. We obtained monthly anthropometric measurements in a cohort of 957 pregnant women from Tanzania who were HIV infected. We estimated the weekly rate of weight gain at various points during the second and third trimesters of pregnancy and computed rate differences between levels of sociodemographic, nutritional, immunologic, and parasitic variables at the first prenatal visit. The change in mid-upper arm circumference (MUAC) from baseline to delivery was also examined. The rate of weight gain decreased progressively during pregnancy. There was an average decline of 1 cm in MUAC between weeks 12 and 38. Lower level of education and helminthic infections at first visit were associated with decreased adjusted rates of weight gain during the third trimester. High baseline MUAC, not contributing to household income, lower serum retinol and selenium concentrations, advanced clinical stage of HIV disease, and malaria infection were related to decreased rates of weight gain during the second trimester. Low baseline CD4 T-cell counts were related to a poorer pattern of weight gain throughout pregnancy. Prevention and treatment of parasitic infections and improvement of nutritional status are likely to enhance the pattern of gestational weight gain among HIV-infected women.     

Evaluation of new blood culture processing systems

The Antimicrobial Removal Device (ARD; Marion Scientific) was evaluated in vitro with simulated blood culture samples in fresh blood and clinically with samples from potentially septic patients to test its ability to remove antimicrobial agents and recover bacteria from blood culture specimens containing these drugs. In simulated specimens, the ARD was evaluated for adverse affects on microorganisms as well as compared with lysis-centrifugation (Isolator; Du Pont Co.), biphasic brain heart infusion bottles, and tryptic soy broth bottles for antimicrobial inactivation and organism recovery. There was no adverse effect of the ARD on organisms during a 4-h test period. The ARD was the only system to actually inactivate antimicrobial agents and removed greater than 99.2% of all antimicrobial agents tested from spiked and clinical specimens. Overall, with simulated blood culture specimens, the ARD recovered 90% of bacteria spiked into fresh blood containing antimicrobial agents, Isolator recovered 73%, biphasic brain heart infusion bottles recovered 31%, and tryptic soy broth bottles recovered 24%. In the clinical study, 43 of 86 clinically significant isolates were recovered only by ARD-assisted processing, 6 were recovered only by conventional processing, and 37 were recovered by both methods (the advantage of ARD processing over conventional processing in the clinical study was significant at P less than 0.001). Both clinical and simulated specimens demonstrated the ARD-associated blood culture processing to be the most efficient method for the isolation of microorganisms from specimens containing antimicrobial agents.     

Value of terminal subcultures for blood cultures monitored by BACTEC 9240.

Blood cultures collected in BACTEC Plus Aerobic/F bottles and BACTEC Plus Anaerobic/F bottles were monitored for 5 days by BACTEC 9240 and subsequent terminal subcultures. Of the 13,471 bottles subcultured, 11.0% (1,477 of 13,471) were culture positive. Of these, 94.0% (1,388 of 1,477) were detected by BACTEC 9240; the additional 6.0% (89 of 1,477) were considered to be false negatives by BACTEC 9240 since they were detected by terminal subculture only. The false-negative bottles consisted of 17 BACTEC Plus Aerobic/F and 72 BACTEC Plus Anaerobic/F bottles, accounting for 2.2 (17 of 786) and 10.4% (72 of 691) of the total positive aerobic and anaerobic bottles, respectively. The positive blood culture bottles most frequently not detected by BACTEC 9240 grew Pseudomonas spp. (24), Staphylococcus spp. (21), and yeasts (24). Of the 86 blood cultures represented by the 89 false-negative bottles, 41 would not have been identified as positive since the other bottle in the blood culture set was either a false negative or a true negative. In general, terminal subcultures of false-negative BACTEC bottles had heavy growth, indicating that BACTEC Plus media were able to support the growth of microorganisms, but the BACTEC 9240 instrument was unable to detect this growth.     

Evaluation of Mycotrim-GU for isolation of Mycoplasma species and Ureaplasma urealyticum.

The Mycotrim-GU (Hana Biologics, Berkeley, Calif.) biphasic culture system and a conventional system were compared for their ability to detect Ureaplasma urealyticum and Mycoplasma species in 100 clinical specimens. Both systems detected 18 Mycoplasma spp. isolates. The average colony detection time was 1.9 days with the Mycotrim-GU and 2.3 days with the conventional system. The Mycotrim-GU agar detected all 33 U. urealyticum isolates recovered in the study, and the conventional agar detected 31. In addition to the U. urealyticum isolates recovered from the agar, there were several specimens that, although they did not grow colonies on the agar, gave an alkaline broth change. Of these specimens, two were found with the conventional system and seven were found with the Mycotrim-GU. The average detection time of U. urealyticum colonies was 2.0 days for the conventional agar and 1.7 days for the Mycotrim-GU. The Mycotrim-GU offers several advantages over the conventional system: it is commercially available, consists of a one-flask system which is ready to use, has a significantly longer shelf life, and is cost competitive. This study showed the Mycotrim-GU to be an effective system for detecting the genital mycoplasmas.     

Bacterial growth and killing in chronic ambulatory peritoneal dialysis fluids.

We determined the ability of Staphylococcus epidermidis, Staphylococcus aureus, and Escherichia coli to survive and grow in peritoneal dialysis fluids from patients undergoing chronic ambulatory peritoneal dialysis. Staphylococci did not survive in commercially available dialysis solutions but grew readily in peritoneal effluents obtained from patients after the dialysis dwell time. The number of CFU doubled 6 and 13 times in 24 h for S. epidermidis and S. aureus, respectively. E. coli grew well in both the pre- and postdialysis peritoneal fluid. Peritoneal macrophages as well as peripheral blood leukocytes inhibited bacterial growth in peritoneal dialysis fluid. However, 10(6) phagocytes per ml were minimally required to obtain a bacteriostatic effect. The addition of serum to peritoneal dialysis fluid increased the antibacterial activity of macrophages and blood leukocytes. The capacity of the aminoglycoside antibiotic tobramycin to reduce bacterial CFU in peritoneal dialysis fluid was only 10% of its bactericidal capacity in standard Mueller-Hinton brush. Peritoneal dialysis fluid had no effect on the antibacterial activity of imipenem.     

Evidence for the involvement of blood flow-related mechanisms in the ovulatory process of the rat

To elucidate whether any relationship exists between ovarian blood flow and ovulation rate, the effects on these parameters were examined in equine chorionic gonadotrophin/human chorionic gonadotrophin (eCG/HCG) (15I U/15I U) primed rats after bilateral ligation and severance of either the ovarian branch of the uterine artery and vein (UL), the ovarian artery and vein (OL) or both sites (UL+OL) in comparison to sham operations. Laser Doppler flowmetry demonstrated the presence of microcirculatory vasomotion and a reduction of blood flow after UL, OL and UL+OL performed during the intervals 0-3 h (78, 66 and 19% of pretreatment values respectively) and 6-9 h (68, 57 and 20%) after HCG. Experiments utilizing radioactive microspheres also indicated decreased ovarian blood flow by UL and OL. Ovulation rate was assessed 20 h after HCG in animals where ligations had been performed at 0, 3, 6 and 9 h after HCG. No ovulations were seen after UL+OL and significantly decreased ovulation rates ( approximately 50% of sham operated animals) were seen after UL at 0 and 3 h and after OL at 0, 6 and 9 h. Progesterone concentrations in blood 20 h after HCG were reduced by OL but not UL and ovarian weights were unaffected by ligation. It is concluded that acute blood flow reduction during the ovulatory interval reduces ovulation rate in the rat.